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| abstraction > mathematical concept > number > quantity > time > lifetime |
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| lifetime comparison table | ||||||
| Subject | see also | is a kind of | has symbol | has equivalent | has synonym | has definition |
|---|---|---|---|---|---|---|
| time | quantity | A dimension distinguishing past, present, and future. In relativity, time is portrayed as a geometrical dimension, analogous to the dimensions of space. | ||||
| lifetime | half-life | time | τ | half-life / ln 2 | mean life | The time it takes for a sample of identical particles to decay to 1/e of its initial population. |
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